Transcript Development of a model to determine preferences for feed ingredients...

Development of a model to determine preferences for feed ingredients in young pigs
*,1
Heugten ,
1
Heugten ,
1
Zhang ,
2
Roura
E. van
K. Ange-van
W.
and E.
1North Carolina State University, Raleigh, NC; 2Lucta SA, Barcelona, Spain
M121
NC STATE UNIVERSITY
No choice – comparison of the
right vs. the left feeder
Materials and Methods
formulated %
Soybean meal, without hulls
85.86
Lysine - HCl
0.18
Methionine, DL
0.12
Dicalcium phosphate
3.98
Limestone
1.54
Salt
1.25
Copper sulfate
0.20
Vitamin and mineral premix
0.62
Corn oil
6.24
 Diets were identical
with the exception of
grain source (60% of
the diet)
 The concentrate
contributed 1.10%
lysine, 0.70% Ca, and
0.53% P to the total
diet
450
400
350
300
250
200
150
100
50
0
P = 0.07
P = 0.20
P = 0.21
P = 0.22
P = 0.87
Left
Right
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48
72
Time, h
96
Mean
Distribution of preferences
Keywords: Pigs, Preference, Feedstuffs
300
200
e
400
M
or
Corn
Rice
90
500
80
P < 0.001
70
P < 0.001
60
600
P = 0.02
P < 0.001
50
700
P < 0.001
40
800
10
 22 weanling pigs were adjusted to solid feed for 21 days
(corn-soybean meal based)
 Pigs were then housed one pig per pen
 Each pen contained two identical feeders
 Pigs were offered either a corn based diet in both feeders
per pen or a rice based diet for 4 days (no choice)
 Pigs were then offered a choice between corn and rice
based diets for 3 days
 Feeders were distributed such that half of the feeders
contained corn on the pigs’ right side and half on the pigs’
left side
 Feed disappearance was measured daily
10
8
6
4
2
0
Frequency
 Several methods to determine palatability in pigs exist,
including the use of multi-choice arenas (Parfet and
Gonyou, 1991), T-maze method (McLaughlin et al., 1983),
and double-choice methods.
 Development of a model to test palatability of feed
ingredients will allow us to create a data base of the
palatability of different ingredients and flavors
 We can further screen potential palatability enhancers
which can ultimately increase feed intake and pig
performance
Preference of corn vs. rice
during a 3 day choice period
Materials and Methods
Feed disappearance, g/d
Introduction
(Rice as % of total for the 3-d period)
30
The objective of this study was to develop a model in young pigs to evaluate preferences for feed ingredients.
Twenty-two pigs (BW = 8.33 ± 0.10 kg) were adjusted to solid feed (corn-soybean meal based) for 21 d and
subsequently housed one pig per pen. Each pen contained two identical feeders, positioned side-by-side.
During the first four days, pigs were offered one of two complete diets with either corn or rice as the major
grain source (60% of the diet) in both feeders. Diets were identical with the exception of grain source and
grains were ground through the same screen. Thus, pigs were not offered a choice and this period served to
determine potential side preferences (i.e., the left versus the right feeder) and to determine whether previous
exposure to grains had an effect on subsequent preference when offered a choice. Following this initial
period, pigs were offered the rice-based diet (Rice) in one feeder and the corn-based diet (Corn) in the other
feeder. Pigs were allowed to consume feed freely from either feeder for 72 hr and feed disappearance was
measured every 24 hr. Pigs consumed 249 g/d from the left feeder and 329 g/d from the right feeder (P =
0.22) during the four-day period when no choice was offered. Total consumption of Rice (556 g/d) was not
different (P = 0.34) from Corn (600 g/d) during the pretest period. When offered a choice, pigs clearly
preferred Rice compared to Corn on day 1 (489 vs 248 g/d; P = 0.02), d 2 (589 vs 155 g/d; P < 0.001), d 3
(680 vs 132 g/d; P < 0.001), and overall (586 vs 178 g/d; P < 0.001). Preference was impacted by prior
exposure only on d 1 (P = 0.02). Pigs previously exposed to Corn highly preferred Rice (623 vs 159 g/d; P <
0.001), but pigs previously exposed to Rice did not demonstrate a preference (336 vs 355 g/d; P = 0.75).
Results of this study demonstrate that prior exposure will impact preferences briefly and that two days is
adequate for determining preferences for ingredients and flavors in future studies.
Ingredient
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Development of a model to determine preferences for feed ingredients in young pigs. E. van
Heugten*,1, K. Ange-van Heugten1, W. Zhang1, and E. Roura2. 1North Carolina State University, Raleigh, NC;
2Lucta SA, Barcelona, Spain.
Composition of the concentrate (40% of the final diet)
Feed disappearance, g/d
Abstract
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0
24
Objective
48
72
Time, h
0-48
0-72
Conclusions
Impact of previous exposure
on preference
Develop a model in young pigs to evaluate
preferences for feed ingredients
Feed disappearance, g/d
800
700
*
*
*
*
*
*
*
**
*
* P < 0.01
** P < 0.05
600
NS
500
Corn
Rice
400
 Pigs clearly preferred the rice based diet compared to the
corn based diet on all three days of measurement
 Preference was impacted by prior exposure only on d 1
 Pigs previously exposed to the corn based diet highly
preferred the rice based diet, but pigs previously exposed
to the rice diet did not demonstrate a preference
 Results demonstrate that prior exposure impacts
preferences briefly
 Results further indicate that two days is adequate for
determining preferences for ingredients and flavors in
future studies
300
200
Literature Cited
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0
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72 0-48 0-72 24
Previous exposure: Corn based diet
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72 0-48 0-72

Parfet, K. A., and H. W. Gonyou. 1991. Attraction of newborn piglets to auditory, visual, olfactory and
tactile stimuli. J. Anim. Sci. 69:125-133.

McLaughlin, C. L., C. A. Baile, L. L. Buckholtz, and S. K. Freeman. 1983. Preferred flavors and
peformance of weanling pigs. J. Anim. Sci. 56:1287-1293.
Rice based diet